package com.hy.study.tree;

public class BinaryTreeDemo {
    public static void main(String[] args) {
        //创建二叉树
        BinaryTree binaryTree = new BinaryTree();

        HeroNode root = new HeroNode(1, "宋江");
        HeroNode node2 = new HeroNode(2, "吴用");
        HeroNode node3 = new HeroNode(3, "卢俊义");
        HeroNode node4 = new HeroNode(4, "林冲");
        HeroNode node5 = new HeroNode(5, "关胜");

        root.setLeft(node2);
        root.setRight(node3);
        node3.setRight(node4);
        node3.setLeft(node5);

        binaryTree.setRoot(root);
        System.out.println("----start-----前序遍历----");

        //前序遍历
        binaryTree.preOrder();// 1 2 3 4

        System.out.println("----end-----前序遍历----");
        //中序遍历

        System.out.println("----start-----中序遍历----");
        binaryTree.infixOrder();// 2 1 3 4
        System.out.println("----end-----中序遍历----");
        System.out.println("----start-----后序遍历----");
        binaryTree.postOrder();// 2 4 3 1
        System.out.println("----end-----后序遍历----");
        System.out.println("-----前序遍历查找得到:" + binaryTree.preOrderSearch(4));
        System.out.println("-----中序遍历查找得到:" + binaryTree.infixOrderSearch(4));
        System.out.println("-----后序遍历查找得到:" + binaryTree.postOrderSearch(4));

        binaryTree.delete(3);
        binaryTree.preOrder();// 1 2 3 4
    }

}

//定义二叉树
class BinaryTree {
    public BinaryTree() {
    }

    private HeroNode root;

    public HeroNode getRoot() {
        return root;
    }

    public void setRoot(HeroNode root) {
        this.root = root;
    }

    public BinaryTree(HeroNode root) {
        this.root = root;
    }

    /**
     * 二叉树 开始前序遍历
     */
    public void preOrder() {
        if (this.root != null) {
            this.root.preOrder();
        } else {
            System.out.println("二叉树为空无法遍历");
        }
    }

    /**
     * 二叉树 中序遍历
     */
    public void infixOrder() {
        if (this.root != null) {
            this.root.infixOrder();
        } else {
            System.out.println("二叉树为空无法遍历");
        }
    }

    /**
     * 二叉树 后续遍历
     */
    public void postOrder() {
        if (this.root != null) {
            this.root.postOrder();
        } else {
            System.out.println("二叉树为空无法遍历");
        }
    }

    /**
     * 前序遍历
     *
     * @param no
     * @return
     */
    public HeroNode preOrderSearch(int no) {
        if (root != null) {
            return root.preSearch(no);
        } else {
            return null;
        }

    }

    /**
     * 中序遍历
     *
     * @param no
     * @return
     */
    public HeroNode infixOrderSearch(int no) {
        if (root != null) {
            return root.infixSearch(no);
        } else {
            return null;
        }
    }

    /**
     * 后序遍历
     *
     * @param no
     * @return
     */
    public HeroNode postOrderSearch(int no) {
        if (root != null) {
            return root.postSearch(no);
        } else {
            return null;
        }
    }

    /**
     * 删除节点
     */
    public void delete(int id){
        if(root!=null){
          if(root.getNo()==id){//如果root 就是需要删除的
              root=null;
          }else {
              root.delete(id);
          }
        }else {
            System.out.println("空树无法删除");
        }
    }
}

class HeroNode {
    private int no;
    private String name;
    private HeroNode left;
    private HeroNode right;

    public HeroNode(int no, String name) {
        this.no = no;
        this.name = name;
    }

    public int getNo() {
        return no;
    }

    public void setNo(int no) {
        this.no = no;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public HeroNode getLeft() {
        return left;
    }

    public void setLeft(HeroNode left) {
        this.left = left;
    }

    public HeroNode getRight() {
        return right;
    }

    public void setRight(HeroNode right) {
        this.right = right;
    }

    @Override
    public String toString() {
        return "HeroNode{" +
                "no=" + no +
                ", name='" + name + '\'' +
                '}';
    }

    /**
     * 前序遍历
     */
    public void preOrder() {
        System.out.println(this);//先输出父节点
        //递归向左子树前序遍历
        if (this.left != null) {
            this.left.preOrder();
        }
        if (this.right != null) {
            this.right.preOrder();
        }
    }

    /**
     * 中序遍历
     */
    public void infixOrder() {
        //递归向左子树中序遍历
        if (this.left != null) {
            this.left.infixOrder();
        }
        System.out.println(this);//输出当前节点 父节点
        if (this.right != null) {
            this.right.infixOrder();
        }
    }

    /**
     * 后序遍历
     */
    public void postOrder() {
        if (this.left != null) {
            this.left.postOrder();
        }
        if (this.right != null) {
            this.right.postOrder();
        }
        System.out.println(this);//输出当前节点 父节点
    }

    /**
     * 前序遍历查找
     *
     * @param no
     * @return
     */
    public HeroNode preSearch(int no) {
        if (this.getNo() == no) {
            return this;
        }
        HeroNode resultNode = null;
        if (this.getLeft() != null) {
            resultNode = this.getLeft().preSearch(no);
        }
        if (resultNode != null) {
            return resultNode;
        }
        if (this.getRight() != null) {
            resultNode = this.getRight().preSearch(no);
        }
        return resultNode;
    }

    /**
     * 中序遍历查找
     *
     * @param no
     * @return
     */

    public HeroNode infixSearch(int no) {
        HeroNode resultNode = null;
        if (this.getLeft() != null) {
            resultNode = this.getLeft().infixSearch(no);
        }
        if (resultNode != null) {
            return resultNode;
        }
        if (this.getNo() == no) {
            return this;
        }
        if (this.getRight() != null) {
            resultNode = this.getRight().infixSearch(no);
        }
        return resultNode;
    }

    /**
     * 后序遍历
     *
     * @param no
     * @return
     */
    public HeroNode postSearch(int no) {
        HeroNode resultNode = null;
        if (this.getLeft() != null) {
            resultNode = this.getLeft().postSearch(no);
        }
        if (resultNode != null) {
            return resultNode;
        }
        if (this.getRight() != null) {
            resultNode = this.getRight().postSearch(no);
        }
        if (resultNode != null) {
            return resultNode;
        }
        if (this.getNo() == no) {
            return this;
        }
        return resultNode;

    }

    /**
     * 删除某个节点
     *
     * @param no
     */
    public void delete(int no) {
        /**
         * 左子树不为空，且正好是删除元素 ，将这个节点的子树都删掉
         */
        if (this.getLeft() != null && this.getLeft().getNo() == no) {
            this.setLeft(null);
            return;
        }
        if (this.getRight() != null && this.getRight().getNo() == no) {
            this.setRight(null);
            return;
        }
        //向左子树递归删除
        if (this.getLeft() != null) {
            this.getLeft().delete(no);
        }
        //向右子树递归删除
        if (this.getRight() != null) {
            this.getRight().delete(no);
        }

    }
}
